Adds nickname and use_nickname to "my profile"

config/locales/en.yml

@@ -60,6 +60,8 @@ en:
       change_credentials_link: "Change my credentials"
       first_name_label: "First Name"
       last_name_label: "Last Name"
+      use_nickname_label: "Use nickname"
+      nickname_label: "Nickname"
   recaptcha:
     errors:
       verification_failed: "The captcha verification failed"